Chimpanzee pinworm, Enterobius anthropopitheci (Nematoda: Oxyuridae), maintained for more than twenty years in captive chimpanzees in Japan

The chimpanzee pinworm, Enterobius anthropopitheci (Gedoelst, 1916), was found in chimpanzees, Pan troglodytes, reared in Kumamoto Primate Research Park, Sanwa Kagaku Kenkyusho Co., Ltd., Kumamoto, Japan, in 2006. Because the chimpanzees in this institution originated from chimpanzees imported from Africa before 1984, it is considered that E. anthropopitheci infection has persisted for more than 20 yr in the chimpanzees. Analysis of pinworm specimens preserved in the institution revealed that transition of predominant pinworm species occurred, responding to the change of anthelmintics used for pinworm treatment. Present dominance of E. anthropopitheci is surmised to be caused by fenbendazole, which has been adopted from 2002. Scarcity of mixed infection with E. anthropopitheci and Enterobius vermicularis suggests interspecific competition between the pinworms.     

A redescription of <Emphasis Type="Italic">Protospirura muricola</Emphasis> Gedoelst, 1916 (Nematoda: Spiruridae), a parasite of murid rodents

The spirurid nematode Protospirura muricola Gedoelst, 1916 is redescribed from Acomys dimidiatus (Desmarest) from the St Katherine Protectorate, Sinai, Egypt. Egyptian material closely resembled specimens of P. muricola from African mammals re-examined in this study, as well as conforming to published reports of this species. P. muricola with two denticles on each lateral lobe of the pseudolabia and six pairs of postanal papillae is closest to P. pseudomuris Yokohata & Abe, 1989, but can be readily distinguished in having the right spicule shorter than the left. The significance of the characteristics of the head and mouth, and of the male spicules, in characterising Protospirura Seurat, 1914 is evaluated. P. muricola, an African parasite of rodents, appears to have spread globally with synanthropic rat final hosts and possibly with the cosmopolitan dermapteran intermediate host Leucophaea maderae (Fabr.).     

Redescription of Ichthyouris bursata Moravec & Prouza, 1995 (Nematoda: Pharyngodonidae), a parasite of wild and aquarium-reared discus Symphysodon spp. (Osteichthyes)

The oxyuroid nematode Ichthyouris bursata Moravec & Prouza, 1995 (Pharyngodonidae) was recorded from the intestine of discus (Symphysodon spp. and hybrids) cultured in discus farms in Bangkok and Nonthaburi, central Thailand, during 2006 and 2007. This material made it possible to study in detail the morphology of this little known parasite species, using both light and scanning electron microscopy (the latter not previously used for the male). The SEM examination showed taxonomically important morphological features not previously reported or erroneously described, including the presence of three bilobed lips, a pair of sclerotised plate-like structures and a median cone-shaped outgrowth on the posterior cloacal lip, short 'hairs' on the cloacal lips, digital phasmids in the male and, sometimes, up to two filaments on the egg poles. This species is of South American origin, which was confirmed by its recent record from a free-living blue discus S. aequifasciatus Pellegrin in Brazil. The reproduction and transmission of I. bursata in the conditions of aquarium tanks is probably permitted by the direct (homoxenous) life-cycle of this parasite.     

The mitochondrial genome sequence of Enterobius vermicularis (Nematoda: Oxyurida)--an idiosyncratic gene order and phylogenetic information for chromadorean nematodes

The complete mitochondrial genome sequence was determined for the human pinworm Enterobius vermicularis (Oxyurida: Nematoda) and used to infer its phylogenetic relationship to other major groups of chromadorean nematodes. The E. vermicularis genome is a 14,010-bp circular DNA molecule that encodes 36 genes (12 proteins, 22 tRNAs, and 2 rRNAs). This mtDNA genome lacks atp8, as reported for almost all other nematode species investigated. Phylogenetic analyses (maximum parsimony, maximum likelihood, neighbor joining, and Bayesian inference) of nucleotide sequences for the 12 protein-coding genes of 25 nematode species placed E. vermicularis, a representative of the order Oxyurida, as sister to the main Ascaridida+Rhabditida group. Tree topology comparisons using statistical tests rejected an alternative hypothesis favoring a closer relationship among Ascaridida, Spirurida, and Oxyurida, which has been supported from most studies based on nuclear ribosomal DNA sequences. Unlike the relatively conserved gene arrangement found for most chromadorean taxa, E. vermicularis mtDNA gene order is very unique, not sharing similarity to any other nematode species reported to date. This lack of gene order similarity may represent idiosyncratic gene rearrangements unique to this specific lineage of the oxyurids. To more fully understand the extent of gene rearrangement and its evolutionary significance within the nematode phylogenetic framework, additional mitochondrial genomes representing a greater evolutionary diversity of species must be characterized.     

Redescription, synonymy, and new records of Vexillata noviberiae (Dikmans, 1935) (Nematoda: Trichostrongylina), a parasite of rabbits Sylvilagus spp. (Leporidae) in the United States

Vexillata noviberiae (Dikmans, 1935) (Trichostrongylina: Heligmosomoidea), originally described as a parasite of Sylvilagus floridanus from Louisiana, is redescribed from material collected from Sylvilagus palustris in Florida and from S. floridanus in Kansas. New morphometric and morphological data are provided. Stunkardionema halla Arnold, 1941, described from S. floridanus from Kansas and New York, is proposed as a junior synonym of V. noviberiae. These findings confirm the occurrence of V. noviberiae as a parasite of rabbits and its wide distribution range in North America.     

Redescription of Heliconema africanum (Linstow, 1899) n. comb. (Nematoda: Physalopteridae), a nematode parasite of freshwater eels (Anguilla spp.) in South Africa

The little-known nematode species Heliconema africanum (Linstow, 1899) n. comb. (Physalopteridae) is redescribed based on light and scanning electron microscopical examinations of specimens collected from the stomach of the African longfin eel Anguilla mossambica (Peters) in the Nahoon River, Eastern Cape Province, South Africa. This species, previously misidentified as Heliconema longissimum (Ortlepp, 1922), is a common parasite of eels in South Africa. The systematic status of H. longissimum, a species originally described from unidentified Australian snakes, is unclear and probably several morphologically closely related species have been included under this name.     

Redescription of Cosmocephalus tanakai Rodrigues & Vicente (Nematoda: Acuariidae), a parasite of the southern black-backed gull in New Zealand

Abstract

Cosmocephalus tanakai is redescribed from specimens found in the oesophagus of Larus dominicanus from the South Island of New Zealand. The male is characterised by nine pairs of pedunculate subventral caudal papillae plus two pairs of sessile papillae, and a pair of bicuspid papillae three-quarters of the way down the body. The female too has the pair of posteriad bicuspid papillae, plus a button-like terminal caudal process. A key to the species of Cosmocephalus is given.     

Broad infectivity of Leidynema appendiculatum (Nematoda: Oxyurida: Thelastomatidae) parasite of the smokybrown cockroach Periplaneta fuliginosa (Blattodea: Blattidae)

Host specificity of parasites is important for the understanding of evolutionary strategies of parasitism that would be a basis of predictions of the disease expansion when parasitized hosts invade new environments. The nematode order Oxyurida is an interesting parasite group for studying the evolution of parasitism as it includes parasites of both invertebrates and vertebrates. In our survey, we found that the smokybrown cockroach Periplaneta fuliginosa was primarily infected with only one nematode species Leidynema appendiculatum. In two cases, L. appendiculatum was isolated from two additional cockroach species Pycnoscelus surinamensis, sold in Japan as a reptile food, and Blatta lateralis, captured in the field and cultured in the laboratory. Inoculation of L. appendiculatum into three additional cockroach species P. japonica, Blattella nipponica, and P. surinamensis also resulted in parasitism. Infection prevalence was high, and timing of postembryonic development from hatched nematode larva to mature adult in these hosts was identical with that in P. fuliginosa. While ecological interactions strongly determine the host range, such broad infectivity is still possible in this parasitic nematode.     

Redescription of Cruzia americana Maplestone, 1930 (Nematoda: Kathlaniidae) a parasite of Didelphis virginiana (Kerr) (Mammalia: Didelphidae) in the USA

Systematic Parasitology - Cruzia americana Maplestone, 1930 is a common nematode parasite of opossums in North America. However, our present knowledge on the morphology of this species is still...     

Redescription of Three Ektaphelenchus Species (Nematoda: Aphelenchina)

Three Ektaphelenchus species with unusual spicules are redescribed. Ektaphelenchus obtusus and E. riograndensis are redescribed from newly discovered material in the collection of the USDA Forest Service RMRS. Lectotype slides are designated for both species. Ektaphelenchus obtusus is characterized by a set-off head, lips of unequal size, double rows of oocytes and spermatocytes, and a hooked spicule terminus. Ektaphelenchus riograndensis is distinguished by a rounded head with six equal lips, and spicules with a large, rounded apex, and recurved terminus. A bursa and gubernaculum are absent in both species. Ektaphelenchus scolyti is redescribed from type material deposited in the collection of Rothamsted Experimental Station. It is characterized by a well set-off head, double rows of oocytes and spermatocytes, and spicules with a hooked terminus. A bursa and gubernaculum are absent.     

Etude morphologique de Austroxyuris finlaysoni (Oxyuridae,Nematoda), parasite de Petauroides volans (Petauridae,Marsupiala)

Résumé Austroxyuris finlaysoni Johnston & Mawson, 1938, un oxyure parasite du caecum et du gros intestin d'un marsupial pétauridé australien, Petauroides volans Kerr, est redécrit à partir d'un matériel nouveau. Les caractéristiques du genre Austroxyuris Johnston & Mawson, 1938 sont ensuite discutées. Ces oxyures pratiquent de manière facultative une forme d'insémination traumatique que l'on peut considérer comme relativement primitive.

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Austroxyuris finlaysoni Johnston & Mawson, 1938, a pinworm parasite of an Australian marsupial, Petauroides volans Kerr, is redescribed. Morphological study of this species reveals: (i) the presence of very specialized oesophageal teeth in both sexes, (ii) the presence of an area rugosa and of a differentiated caudal bursa in the males, and (iii) the presence of a vagina vera modified into a spermatic pouch used during traumatic insemination. The morphological and biological characteristics of the genus Austroxyuris Johnston & Mawson, 1938 are discussed. The members of this genus occasionally use a form of traumatic insemination which can be considered relatively primitive.

     

Redescription of Cardiosporidium cionae (Van Gaver and Stephan, 1907) (Apicomplexa: Piroplasmida), a plasmodial parasite of ascidian haemocytes

Cardiosporidium cionae (Apicomplexa), from the ascidian Ciona intestinalis L., is redescribed with novel ultrastructural, phylogenetic and prevalence data. Ultrastructural analysis of specimens of C. intestinalis collected from the Gulf of Naples showed sporonts and plasmodia of C. cionae within the host pericardial body. Several merogonic stages and free merozoites were found in the pericardial body, together with sexual stages. All stages showed typical apicomplexan cell organelles, i.e. apicoplasts, rhoptries and subpellicular microtubules. Merogonic stages of C. cionae were also produced inside haemocytes. A fragment of the rSSU gene of C. cionae was amplified by PCR using DNA extracted from the pericardial bodies. The amplified product showed closest affinity with other apicomplexan representatives and a 66bp unique insertion, specific for C. cionae, at position 1644. Neighbour-joining phylogenetic analysis placed C. cionae in a clade with other piroplasm genera, including Cytauxzoon, Babesia and Theileria spp. The parasite was found in different populations of C. intestinalis with highest prevalence in October-November. Ultrastructural and DNA data showed that the organism, described in 1907 from the same host but not illustrated in detail, is a member of a novel marine apicomplexan radiation of tunicate parasites.     

Redescription of Monhystrella parvella (Filipjev) comb.n. (Nematoda, Monhysteridae)

The type of material of Monhystrella parvella (Filipjev, 1931) comb.n. from Abyssinia (Ethiopia) is redescribed and figured in detail. Data on the genital system and the ontogeny of this species are given. Monhystera filiformis sensu Gerlach, 1951 nec Bastian, 1865 of the Black Sea at Pomorie (Bulgaria) is synonymised with M. parvella . The Black Sea specimens have a shorter pharynx, a longer tail and differ also from the Abyssinian specimens in the shape of the tail and the spinneret outlet.     

Pterygodermatites (Mesopectines) senegalensis n. sp. (Nematoda, Rictulariidae), a parasite of Mastomys huberti (Rodentia, Muridae) in Senegal

Pterygodermatites (Mesopectines) senegalensis n. sp. (Nematoda: Rictulariidae) is described from Mastomys huberti in Senegal. It differs from other species of the subgenus by the morphology of the head, which exhibits 4 simple cephalic papillae and a nearly axial buccal opening, the length of the spicules, the number of precloacal cuticular formations, and the absence of cephalic apophyses.     

The importance of host ecology in thelastomatoid (Nematoda: Oxyurida) host specificity

An experimental investigation of host specificity within the Thelastomatoidea is presented by means of a comparison of the thelastomatoids of two panesthiine cockroaches, Panesthia cribrata and P. tryoni tryoni, with those of other log-dwelling arthropods and those of leaf litter dwelling arthropods found near by. 145 log-dwelling and leaf-litter dwelling arthropods, representing adjacent ecological niches, were collected from Lamington National Park, Queensland, Australia. A high degree of thelastomatoid species sharing (19 incidences from 26 specimens) occurs between log-dwelling arthropods and the two cockroach species. No overlap in thelastomatoid fauna was observed between the log dwelling and leaf-litter dwelling groups. Our results suggest that host specificity of thelastomatoids is largely dictated by host ecology.